By now, most of us know how to recognize the signs that our credit or debit card information has been compromised. Maybe you see some strange activity in your banking app, or an emailed receipt from Amazon for a heinous chaise longue you didn't order.The scam we're talking about today can be much more insidious. It can go on for years while you remain completely unaware, until one day, you get a phone call asking why you haven't made any payments on a mortgage you never signed up for. Welcome to the world of 'synthetic identity fraud'. So how does this scheme work? How can you tell if someone has used your information to take out a fraudulent car loan or mortgage? And what should you do once you've uncovered the scam? GUEST: Jennifer Fiddian-Green, leader of the National Risk and Forensic Advisory Practice at Grant-Thornton LLP